Liquid flow monitoring

ABSTRACT

Apparatus for regulating and monitoring the flow of a liquid/gas fluid mixture such as the type encountered in crude petroleum recovery. The apparatus includes a first expansion enclosure receiving liquid and/or gas input with the first output from said expansion enclosure being applied through a biased valve which allows output flow at greater than predetermined pressures. A second valve member disposed in a second output of the expansion enclosure is operated via a float to close at a predetermined liquid level within said expansion enclosure and to open below such level thereby to allow by-pass flow of gas substance from said second output for later addition to the first output. Flow monitor means responsive to the position of said first valve means provides a flow time indication and/or output record.

United States Patent 1 Butler [451 Jan. 2, 1973 [54] LIQUID FLOWMONITORING Primary Examiner-Alan Cohan Att0meyJoseph C. Kotarski, HenryH. Huth, Robert B. Coleman, Jr., William J. Miller and Dunlap, Laney,Hessin & Dougherty [5 7] ABSTRACT Apparatus for regulating andmonitoring the flow of a liquid/gas fluid mixture such as the typeencountered in crude petroleum recovery. The apparatus includes a firstexpansion enclosure receiving liquid and/or gas input with the firstoutput from said expansion enclosure being applied through a biasedvalve which allows output flow at greater than predetermined pressures.A second valve member disposed in a second output of the expansionenclosure is operated via a float to close at a predetermined liquidlevel within said expansion enclosure and to open below such levelthereby to allow by-pass flow of gas substance from said second outputfor later addition to the first output. Flow monitor means responsive tothe position of said first valve means provides a flow time indicationand/or output record.

7 Claims, 2 Drawing Figures 77 75 70 76 la 4 f QR.

5 52 a 42 N l as J 54 L2 5? 65 5 52 a0 44 Z M 457 FLOW 64 MOM/TOR 1 I2554 l4 1 g I 1 LIQUID FLOW MONITORING BACKGROUND OF THE INVENTION 1.Field of the Invention The invention relates generally to flowindicating devices for fluid conduits and, more particularly, but not byway of limitation, it relates to improved flow/noflow indicatingapparatus for use in automatic oil lease surveillance and monitoringsystems.

2. Description of the Prior Art The prior art includes various types ofautomatic and manually controlled valve assemblies which are used forregulation of fluid output from well heads and the like. In the main,the prior art devices include no designs wherein they are able todistinguish between liquid and gas flow through the output conduit, andsuch inability often results in false flow signals due to continued gasproduction through the output line after the well ceases to pump liquid.Further, several prior designs have been found tobe very susceptible tosticking in the open or full fiow position thereby to render any flowindication erroneous. Such flow valve sticking condition is especiallytroublesome in parrafin producing areas, and many typical installationsinclude an additional check valve at the flow line header to guardagainst such sticking and false generation of flow indication. Anexample of prior art flow monitor of different type is described in theU. S. Pat. No. 3,392,580 in the name of Bain. This device is of asignificantly different structure and function from the invention asdescribed herein.

SUMMARY OF THE INVENTION The present invention contemplates a controlvalve for a liquid flow line which is capable of passing liquid above apredetermined line pressure while allowing gas product by-pass duringflow and/or no-flow line condition. The apparatus consists of anenclosure connected in the liquid line to receive input therefrom and toprovide first and second outputs, a first output provides liquid flow toa weight-biased output valve to allow intermittent communication to anoutput liquid line; the second enclosure output is controlled by a floatvalve responsive to a predetermined level of liquid within the enclosureto allow flow of gas product by by-pass conduit for subsequentconnection back into the output liquid line. Flow monitoring apparatusresponsive to the position of the weight-biased valve provides anindication of the fiow/no-flow condition of the liquid flow line.

Therefore, it is an object of the present invention to provide a flowindicating device which generates reliable indication for all producingconditions including wells that produce very low liquid volumes withgas/oils ratios which extend over an extremely wide range.

It is a further object of the present invention to provide an apparatusfor gas-liquid separation which is designed to by-pass all gas in theevent of a no-flow liquid condition.

It is yet another object of the present invention to provide a liquidline flow valve which is simple yet positive and which will also act asa flow line check.

Finally, it is an object of the present invention to provide a flowregulation and recording apparatus which is inexpensive yet highlyreliable in operation, and which effectively combats a common problem offailure to indicate a fluid flow line closed in the no-flow condition.

LII

Other objects and advantages of the invention will be evident from thefollowing detailed description when read in conjunction with theaccompanying drawing which illustrates the invention.

BRIEF DESCRIPTION OF THE DRAWING DETAILED DESCRIPTION OF THE PREFERRED AEMBODIMENTS Fluid flow such as a mixture of crude oil liquid and gassubstance recovered from an oil well is present in an input conduit 10for input to a flow regulation device 12 which, in turn, is connected toan output flow conduit 14.'The flow regulation device 12 furtherconsists of a liquid chamber 16, a gas by-pass conduit 18 and a liquidflow pipe 20 connected to a flow valve 22 which provides output to apipe 24 and output conduit 14.

The chamber 16 may be such as a cylindrical tank having a side wall 26and base plate 28 with a top cover member 30 secured thereover as bywelding to provide a gas-tight sealed enclosure. The cover member 30 mayinclude such as a cylindrical neck portion 32 which is formed with aninner annular flange 34, and which includes a groove 36 for receivingone side or annular edge of a groove coupling 38 of standard type. Acover plate 40 including an annular shoulder 42 then receives anopposite annular edge, of groove coupling 38 to maintain over plate 40in tightly-sealed relationship to an upper surface 44 of neck portion32.

The cover plate 40 is formed with a central hole 46 through which a pipemember 48 is received perpendicularly therethrough and secured as bywelding to provide a sealed joinder. The pipe member 48 houses a checkvalve assembly which consists of upper and lower valve balls 50 and 52coactively positioned adjacent a-valve seat54 secured thereacross andhaving both upper and lower valve seats 56 and 58 for receivingrespective valve balls 50 and 52. The upper valve ball 50 serves a checkfunction as force of gravity will maintain the valve ball 50 downagainst seat 56; however, lower valve ball 52 is only urged into closingrelationship with valve seat 58 when so forced by pusher pad 60 securedto the end of a shaft 62 which, in turn, is supported by a float 64, ahollow bulb or such of con ventional design. A plurality of gas escapeorifices 65" are formed in pipe member 48 just beneath the valve seat54. The lower end of pipe member 48 includes a pair of annular shoulders66 and 68 secured therein in spaced relationship, shoulders 66 and 68serving to maintain the shaft 62 and bulb 64 in freely sliding, captivealignment beneath valve ball 52.

The upper end of pipe member 48 includes a cap portion 70 which mayinclude a vertically disposed threaded screw 72 to allow cleaning oraccess, as well as an outlet 74 which connects gas flow to by-passconduit 18. The by-pass conduit 18 may consist of standard pipe andfittings suitable for oil field use or other material as may be adaptedfor whatever the particular application. A pipe section 76 is securedwithin outlet 74 and joined via connector 78 through pipe section 80,elbow 82, and a pipe section 84 to a pipe coupling 86 which connectsinto the outlet line 14. The size and type of pipe connectionconstituting by-pass conduit 18 is not critical, especially in view ofthe fact that the flow indication device 12 is not designed forefficient gas separation during normal flow conditions and it need onlyby-pass gas pressure in the event of the liquid noflow condition.

The liquid outlet pipe 20 applies liquid flow to the valve 22 which maybe any of the well-known types of gate valve. In this particular case,the valve 22 is shown as a swinging-type check valve for variable flowcontrol in response to position of a lever arm 90, connected to a valveoperating shaft 92, which is operable to open the valve when moved inthe direction of arrow 94. Thus, counterclockwise movement of lever arm90, and therefore rotation of operating shaft 92, may be either directlycoupled or it may include gear drive arrangement at a selected ratio toactuate or move the valving member (not shown) within valve 22 to allowincrementing amounts of liquid to flow therethrough. The valve actuatinglever is biased in the clockwise direction by means of a weight 96 whiceis adjustable by a thumb screw 98 along the length of lever 90 therebyto vary the amount of bias applied to valve 22. This amount of weightbias serves to set the amount of forward pressure to begin opening ofthe valve 22, as will be further described below.

A magnet member 100 is suitably suspended as by hinged connection fromthe end of lever 90 to provide an actuating power source for amagnetically responsive reed switch 102, assuspended by a suitablesupport 104 and providing electrical output via lead 106 to a flowmonitor apparatus 108 of conventional type. Referring also to FIG. 2,the condition of valve 22 is apparent from the linkage afforded by leverarm 90 and magnet 100 (shown by dash line in FIG. 2) to provideactuation of reed switch 102 with output via line 106 to an intervaltiming mechanism 110. The interval timing mechanism serves to senseoutput on lead 106 and, in the event the well does not produce liquidsduring a predetermined time interval, an output is applied via line 112as a no-flow signal indication. Thus, in the case as shown in FIG. 2, arecorder drive stage 114 may be de-energized to provide no energizationvia line 116 to a flow recorder 118. A suitable form of flow sensor 120,in contact as shown by dash line linkage 122 with liquid flow throughconduit 24, may be utilized to sense flow volume and provide an outputindication via lead 124 to flow recorder 118. It should be understoodthat there are many types of flow recording and control apparatus whichmay be utilized in conjunction with the flow regulation device 12 ofFIG. 1.

OPERATION The fluid being monitored is present in input conduit andenters the interior 126 of chamber 16, as denoted by liquid 128 having asurface 130. With input flow of liquid, the liquid level or surface 130will rise and the produced fluids will attempt to by-pass throughby-pass conduit 18 due to the additional pressure required to open valve22 as exerted by bias of lever weight 96. Thus, gas components will passthrough orifices 65 in pipe member 48 for by-pass through by-passconduit 18 until the liquid surface 130 carries the float 64 upsufficiently far enough to force valve ball 52 into sealing engagementwithin valve seat 58. Further, either before or after closure of theby-pass valve ball 52, depending upon bias setting, liquid pressurewithin liquid volume 128 will exceed the weight-bias of valve 22 therebyto open valve 22 and allow flow of liquid into the output conduit 14.Also, at this time, lever arm is moved in a counterclockwise directionto position magnet relative to reed switch 102 such that the reed switchis actuated to provide an output via line 106 to flow monitor 108thereby to give proper indication as to the flow condition. All liquidinput to liquid body 128 will be forced to exit through output conduit20, and it will periodically open the valve 22 as the well produces andto provide an output flow with selected record thereof. The valve 22will make and break the magnetic reed switch 102 as it opens and closesthereby to allow the production liquid output to flow therethrough.

In the event that the well does not produce liquids during apredetermined time interval, the reed switch 102 will not make and ano-flow signal will be output on lead 106 to flow monitor 108. The timeinterval may be dependent upon the no-flow scan cycle setting, e.g., asset into the interval timing mechanism 110.

In the event that the well continues to produce gas but is not producingfurther liquids, the biasing should allow gas to displace sufficientliquids from the liquid volume 128 within chamber 16 thereby to allowfloat 64 to drop and release valve ball 52 from its valve seat 7 58. Thevalve ball 52 and valve seat 58 will remain open and by-pass all gasproduction during the particular condition. Thereafter, when liquidproduction is resumed, the liquid level or surface will be raised toraise float 64 and close the by-pass valve ball 52 and valve seat 58such that a flow condition signal will again be monitored whenproduction of liquids is again directed through the valve 22.

The foregoing discloses a novel flow regulating device which may beutilized in various applications wherein a combination of liquid andgaseous products flow through a conduit in varying concentrations andmixtures. While the specification has been particularly directed to theflow of crude oil and natural gas content therein, it should beunderstood that there are many chemical processing and other industrialapplications which may utilize such flow regulating device when there isinvolved the combined flow of both liquid and gaseous product. 7

Changes may be made in the combination and arrangement of elements asheretofore set forth in this specification and shown in the drawings, itbeing understood that changes may be made in the embodiments disclosedwithout departing from the spirit and scope of the invention as definedin the following tion while by-passing said second valve means, whereinsaid second valve means includes: swinging-type check valve meansincluding a lever actuator, weight means adjustably affixed along saidlever to assert predetermined bias force maintaining the valve meansclosed, magnet means affixed to said lever actuator, reed switch meanssecured at a position adjacent the arcuate travel of said lever actuatorat a position where the valve is closed to provide a control output, andflow monitor means controlled in response to said control output.

2. Apparatus as set forth in claim 1 wherein said first valve meanscomprises:

stop valve means including a valve seat member having first and secondvalve seats affixed across said first output connection, and first andsecond valve balls each movably disposed adjacent said respec tive firstand second valve seats, said second valve ball being supported by saidfloat means actuating means. 3. Apparatus as set forth in claim 2wherein: said valve seat member is vertically oriented and said firstand second valve balls are upper and lower,

respectively, such that the first or upper ball acts as a gravityactuated check valve. 4. Apparatus as set forth in claim 1 wherein saidfloat means comprises: hollow bulb means floatable in said liquid; and

rod means having a pusher pad on one end in coating contact with saidfirst valve means and having the opposite end affixed to said floatmeans. 5. Apparatus as set forth in claim 4 which is furthercharacterized to include:

elongated guide means secured beneath said first valve means to extendtherefrom while encompassing said rod means and pusher pad thereby tomaintain the rod means in proper coactive relationship with said firstvalve means. 6. Apparatus as set forth in claim 1 which is furthercharacterized to include:

interval timing means for generating a no flow indicating signal outputin response to detection of said control output indicating valve closurefor greater than a predetermined time. 7. Apparatus as set forth inclaim 6 wherein said first valve means comprises:

stop valve means including a valve seat member having first and secondvalve seats affixed across said first output connection, and first andsecond valve balls each movably disposed adjacent'said respective firstand second valve, seats, said second valve ball being supported by saidfloat means actuating means.

-. Apparatus for regulating flow of fluid having both liquid and gascomponents, comprising: enclosure means having an input connection forreceiving said fluid and sharing first and second output connections,first valve means sealingly disposed in said first output connection,said first valve means being normally open to flow of gas out from saidenclosure means, second valve means sealingly disposed in said secondoutput connector, said second connection valve means being biased closedagainst flow of liquid from said enclosure means, float means includingactuating means coacting with said first valve means, said float meansbeing disposed to float in the liquid within said enclosure meansthereby to actuate said first valve means in accordance with floatlevel, and by-pass conduit means connected to receive gas from saidfirst output connection and to lead said gas to the second outputconnection while by-passing said second valve means, wherein said secondvalve means includes: swinging-type check valve means including a leveractuator, weight means adjustably affixed along said lever to assertpredetermined bias force maintaining the valve means closed, magnetmeans affixed to said lever actuator, reed switch means secured at aposition adjacent the arcuate travel of said lever actuator at aposition where the valve is closed to provide a control output, and flowmonitor means controlled in response to said control output. 2.Apparatus as set forth in claim 1 wherein said first valve meanscomprises: stop valve means including a valve seat member having firstand second valve seats affixed across said first output connection, andfirst and second valve balls each movably disposed adjacent saidrespective first and second valve seats, said second valve ball beingsupported by said floaT means actuating means.
 3. Apparatus as set forthin claim 2 wherein: said valve seat member is vertically oriented andsaid first and second valve balls are upper and lower, respectively,such that the first or upper ball acts as a gravity actuated checkvalve.
 4. Apparatus as set forth in claim 1 wherein said float meanscomprises: hollow bulb means floatable in said liquid; and rod meanshaving a pusher pad on one end in coating contact with said first valvemeans and having the opposite end affixed to said float means. 5.Apparatus as set forth in claim 4 which is further characterized toinclude: elongated guide means secured beneath said first valve means toextend therefrom while encompassing said rod means and pusher padthereby to maintain the rod means in proper coactive relationship withsaid first valve means.
 6. Apparatus as set forth in claim 1 which isfurther characterized to include: interval timing means for generating ano flow indicating signal output in response to detection of saidcontrol output indicating valve closure for greater than a predeterminedtime.
 7. Apparatus as set forth in claim 6 wherein said first valvemeans comprises: stop valve means including a valve seat member havingfirst and second valve seats affixed across said first outputconnection, and first and second valve balls each movably disposedadjacent said respective first and second valve seats, said second valveball being supported by said float means actuating means.